Typical three-dimensional printing technologies include: (1) stereolithography appearance (SLA), which uses photopolymers and irradiation of ultraviolet laser for solidification; (2) selective laser sintering (SLS), which uses granule powder of thermoplastic materials (including polymers like nylon, metals like bronze alloy and titanium alloy, as well as ceramics and glass) to be fused by high power laser; (3) fused deposition modeling (FDM), referring to immediate solidification of sprayed molten thermoplastic materials or eutectic metal powder; (4) laminated object manufacturing (LOM), which uses glue to bond paper or plastic films and then uses laser for formation; (5) ink-jet printing, which sprays fine powder of different materials and uses a bonding agent to cover the materials, and then prints the next layer. Ink-jet printing can also print living cells and biological materials simultaneously to build a three-dimensional biological scaffold with different tissues, or even a living organ.
With the development of dental implantation, there are more and more breakthroughs and applications of core technologies. However, at present, dental implantation is still known for its high price and high risk, because it requires hours of meticulous work by dentists with high technological level and rich operational experience, and a series of tasks including diagnosis, narcosis, selection of implants, tooth preparation modeling, design and production of a dental prosthesis, denture modification and mounting. The application of three-dimensional printing technology in the field of dental implantation is to integrate the technologies of oral scan, oral image processing and three-dimensional printing, and to use technological systems of “digital image capture and reconstruction, CAD/CAM professional design, standard three-dimensional printing and manufacturing, and standardized implantation”, so that, before implantation, the final outcome can be seen from a computer. Before operation, a CT scan of the patient's oral cavity is conducted, and then accurate data is input into a designated design software program, through which, a three-dimensional design of the implantation position is made. Then, an appropriate type of implant is selected, and operation is conducted on the basis of a navigational template to implant the denture and prosthesis. And finally, an ergonomic modification is carried out according to the patient's need. This method can avoid problems like misjudgment of the dentist due to two-dimensional scan image overlay, and reduce risks caused by insufficient skill and experience of the dentist. It can also reduce the workload of dentists while enhancing treatment safety. By sharing digital resources, diagnosis and treatment become “economy”.
The previous processes to make a dental device are time-consuming and labor-intensive, and massive production cannot be fulfilled easily. However, with the current three-dimensional printing and manufacturing technique, the accuracy of a final finished product can be enhanced to the allowance level of only several microns. The three-dimensional printing technology truly provides a big help for the dental industry which requires precision manufacturing. Therefore, a temporary dental prosthesis can be obtained within the time of treatment, and the patient's waiting time is significantly reduced. At present, most three-dimensional printing article used in the domestic dental industry are provided by overseas suppliers, and the cost is very high. Therefore, there is an urgent need to develop a low-cost three-dimensional printing article for making dental products.